Epidemiology of West Nile virus in Africa: an underestimated threat

12openInternationalInternational coauthor/editorBackground West Nile virus is a mosquito-borne flavivirus which has been posing continuous challenges to public health worldwide due to the identification of new lineages and clades and its ability to invade and establish in an increasing number of countries. Its current distribution, genetic variability, ecology, and epidemiological pattern in the African continent are only partially known despite the general consensus on the urgency to obtain such information for quantifying the actual disease burden in Africa other than to predict future threats at global scale. Methodology and principal findings References were searched in PubMed and Google Scholar electronic databases on January 21, 2020, using selected keywords, without language and date restriction. Additional manual searches of reference list were carried out. Further references have been later added accordingly to experts’ opinion. We included 153 scientific papers published between 1940 and 2021. This review highlights: (i) the co-circulation of WNV-lineages 1, 2, and 8 in the African continent; (ii) the presence of diverse WNV competent vectors in Africa, mainly belonging to the Culex genus; (iii) the lack of vector competence studies for several other mosquito species found naturally infected with WNV in Africa; (iv) the need of more competence studies to be addressed on ticks; (iv) evidence of circulation of WNV among humans, animals and vectors in at least 28 Countries; (v) the lack of knowledge on the epidemiological situation of WNV for 19 Countries and (vii) the importance of carrying out specific serological surveys in order to avoid possible bias on WNV circulation in Africa. Conclusions This study provides the state of art on WNV investigation carried out in Africa, highlighting several knowledge gaps regarding i) the current WNV distribution and genetic diversity, ii) its ecology and transmission chains including the role of different arthropods and vertebrate species as competent reservoirs, and iii) the real disease burden for humans and animals. This review highlights the needs for further research and coordinated surveillance efforts on WNV in Africa.openMencattelli, G.; Dior Ndione M.H.; Rosa', R.; Marini, G.; Diagne, C.T.; Diagne, M.M.; Fall, G.; Faye, O.; Diallo, M.; Faye, O.; Savini, G.; Rizzoli, A.Mencattelli, G.; Dior Ndione, M.H.; Rosa', R.; Marini, G.; Diagne, C.T.; Diagne, M.M.; Fall, G.; Faye, O.; Diallo, M.; Faye, O.; Savini, G.; Rizzoli, A

Improving fetal dystocia management using simulation in Senegal: midterm results

Background: Maternal mortality, which constitutes the extreme point of the existing inequality between women in poor and rich countries, remains very high in Africa south of the Sahara. The objective of this study was to introduce a new training approach in Emergency Obstetric and Neonatal Care (EmONC) entered in Senegal to strengthen the skills of healthcare providers.Methods: The approach was based on the skills training using the so-called "humanist" method and "lifesaving skills". Simulated practice took place in the classroom through thirteen clinical stations summarizing the clinical skills on EmONC. The evaluation was done in all phases and the results were recorded in a database to document the progress of each learner.Results: With this approach, 432 providers were trained in 10 months. The increase in technical achievements of each participant was documented through the database. The combination of training based on the model “learning by doing” has ensured learning and mastering all EmONC skills and reduced missed learning opportunities as observed in former EmONC trainings.Conclusions: The impact of training on EmONC indicators and the introduction of this learning modality in basic training are the two major challenges in terms of prospects

Spatial and temporal dynamics of West Nile virus between Africa and Europe

It is unclear whether West Nile virus (WNV) circulates between Africa and Europe, despite numerous studies supporting an African origin and high transmission in Europe. We integrated genomic data with geographic observations and phylogenetic and phylogeographic inferences to uncover the spatial and temporal viral dynamics of WNV between these two continents. We focused our analysis towards WNV lineages 1 (L1) and 2 (L2), the most spatially widespread and pathogenic WNV lineages. Our study shows a Northern-Western African origin of L1, with back-and-forth exchanges between West Africa and Southern-Western Europe; and a Southern African origin of L2, with one main introduction from South Africa to Europe, and no back introductions observed. We also noticed a potential overlap between L1 and L2 Eastern and Western phylogeography and two Afro-Palearctic bird migratory flyways. Future studies linking avian and mosquito species susceptibility, migratory connectivity patterns, and phylogeographic inference are suggested to elucidate the dynamics of emerging viruse

Impact of genetic diversity on biological characteristics of Usutu virus strains in Africa

Usutu virus (USUV) previously restricted to Africa where it caused mild infections, emerged in 2001 in Europe and caused more severe infections among birds and humans with neurological forms, suggesting an adaptation and increasing virulence. This evolution suggests the need to better understand USUV transmission patterns for assessing risks and to develop control strategies. Phylogenetic analysis conducted in Africa showed low genetic diversity of African USUV strains except for one human and the USUV subtype (USUVsub) strains, which exhibited a deletion in the 3′UTR and nucleotide substitutions throughout the genome. Here we analyzed their viral replication in vitro in mosquito and mammalian cells, and vector competence of Culex quinquefasciatus, compared to a reference strain. Growth kinetics of the different strains showed comparable replication rates however variations in replication and translation efficiency were observed. Vector competence analysis showed that all strains were able to infect Culex quinquefasciatus the main peridomestic Culex species in Africa, with detection of USUV viral genomes and infectious particles. Dissemination and transmission were observed only for USUVsub, but infectious particles were not detected in Culex quinquefasciatus saliva. Our findings suggest that genetic variability can affect USUV in vitro replication in a cell type-dependent manner and in vivo in mosquitoes. In addition, the results show that Culex quinquefasciatus is not competent for the USUV strains analyzed here and also suggest an aborted transmission process for the USUVsub, which requires further investigations

Inhibitory Effect of Ursodeoxycholic Acid on Clostridium difficile Germination Is Insufficient to Prevent Colitis: A Study in Hamsters and Humans

Introduction: Bile acids (BA) influence germination and growth of Clostridium difficile. Ursodeoxycholic acid (UDCA), a BA minor in human, used for cholestatic liver diseases, inhibits germination and growth of C. difficile in vitro, but was never tested in vivo with an infectious challenge versus control. We hypothesized that UDCA could prevent CDI. We evaluated the effects of UDCA on C. difficile in vitro and in hamsters, with pharmacokinetics study and with an infectious challenge. Then, we studied CDI incidence in UDCA–treated patients.Methods: We evaluated germination and growth of C. difficile, with 0.01, 0.05, and 0.1% UDCA. We analyzed fecal BA of hamsters receiving antibiotics and UDCA (50 mg/kg/day), antibiotics, or UDCA alone. Then, we challenged with spores of C. difficile at D6 hamsters treated with UDCA (50 mg/kg/day) from D1 to D13, versus control. In human, we analyzed the database of a cohort on CDI in acute flares of inflammatory bowel disease (IBD). As PSC-IBD patients were under UDCA treatment, we compared PSC-IBD patients to IBD patients without PSC.Results:In vitro, UDCA inhibited germination and growth of C. difficile at 0.05 and 0.1%, competing with 0.1% TCA (with 0.1%: 0.05% ± 0.05% colony forming unit versus 100% ± 0%, P < 0.0001). In hamsters, UDCA reached high levels only when administered with antibiotics (43.5% UDCA at D5). Without antibiotics, UDCA was in small amount in feces (max. 4.28%), probably because of UDCA transformation into LCA by gut microbiota. During infectious challenge, mortality was similar in animals treated or not with UDCA (62.5%, n = 5/8, P = 0.78). UDCA percentage was high, similar and with the same kinetics in dead and surviving hamsters. However, dead hamsters had a higher ratio of primary over secondary BA compared to surviving hamsters. 9% (n = 41/404) of IBD patients without PSC had a CDI, versus 25% (n = 4/12) of PSC-IBD patients treated with UDCA.Conclusion: We confirmed the inhibitory effect of UDCA on growth and germination of C. difficile in vitro, with 0.05 or 0.1% UDCA. However, in our hamster model, UDCA was inefficient to prevent CDI, despite high levels of UDCA in feces. Patients with PSC-IBD treated with UDCA did not have less CDI than IBD patients

Les mucosectomies de polypes colorectaux de plus de 20 mm autorisent-elles une prise en charge ambulatoire ?

PARIS7-Xavier Bichat (751182101) / SudocSudocFranceF

Films polymères minces à base de méthacrylate de glycidyle pour l'élaboration d'interfaces immunoréceptrices (étude par résonance de plasmon de surface)

Dans ce travail, nous avons cherché à mettre en évidence l'influence de la méthode de préparation de films minces de polymère pour la biofonctionnalisation de surfaces planes. Dans un premier temps, un polymère réactif, le poly(méthacrylate de glycidyle) p(GMA) a été choisi et sa capacité de fixation vis-à-vis d'une biomolécule modèle l'albumine de sérum bovin a été étudiée. Deux stratégies principales de préparation du film polymère ont été utilisées : la technique du grafting onto et celle du grafting from avec deux voies de synthèse : la polymérisation radicalaire classique (PRC) avec l'amorceur en solution et la polymérisation initiée à partir de la surface avec un amorceur photochimique. Il a été montré que la méthode du grafting from permettait l'obtention de films d'épaisseur plus élevées que la technique du grafting onto avec une meilleure capacité de fixation de biomolécules de BSA. Ces films de p(GMA) se sont révélés relativement hydrophobes, ce qui nous incités à analyser l'influence de la balance hydrophobe/hydrophile des interfaces sur leurs propriétés, dans un second temps. Par la préparation de films copolymères poly(GMA-co-acrylamide) et poly(GMA-co-méthacrylate de glycérol) et la modification des films de poly(GMA) par de l'éthanolamine, l'influence de l'hydrophilie du film sur la capacité de fixation en molécules de BSA et l'activité de reconnaissance moléculaire de celles-ci ont été évaluées. Il a été démontré que par un choix judicieux de la méthode d'hydrophilisation du film polymère, il est possible de réduire considérablement l'adsorption non-spécifique de biomolécules d'où l'obtention de films polymères bioinertes. De plus, les résultats préliminaires ont montré qu'il est possible d'améliorer sensiblement la capacité de reconnaissance moléculaire entre la BSA et son anticorps l'anti-BSAIt is now well accepted that polymeric spacers permit to attach proteins to surfaces efficiently as they carry several binding sites. Moreover, direct attachment of proteins to surfaces might result in the decrease of bioactivity which is critical in the case of the development of biosensors. In this context, we modified gold substrates by polymer grafts via the so-called (i) grafting onto and (ii) grafting from strategies. In (i) preformed polymer chains were attached to the surface, whilst in (ii) surface-confined photopolymerization was performed on either acrylic monomer- or initiator-functionalized gold substrates. The polymer grafts were further biofunctionalized by covalent immobilization of an active protein (bovine serum albumin, BSA). Given the protein-polymer and polymer-gold covalent bonds, the gold/polymer/BSA hybrids permitted to design robust optical biosensors. The modified gold substrates were characterized in terms of chemical composition (X-ray photoelectron spectroscopy), hydrophobicity (contact angle measurements), and polymer coating thickness (surface plasmon resonance, SPR). SPR was also used to monitor in real time the interaction between the grafted antigen to the specific antibody (aBSA). Using unique reactive monomer, glycidyl methacrylate (GMA) in the present case, the implementation of these three methods is assumed to provide polymer films of similar chemical composition but varied interfacial chains conformation. In this respect, influence of polymer chains mobility on the performance of the immunosensing reaction was evaluated. In a further step, hydrophobic/hydrophilic balance of the polymer films was modulated through copolymerization of GMA with acrylamide, and with glycerol methacrylate. It was demonstrated that control over the surface chemical composition of the polymer grafts allows preparing bioinert films, i.e. resistant to non specific adsorption, with enhanced biospecific activityPARIS-EST-Université (770839901) / SudocSudocFranceF

A comparative study on stigma, discrimination, and life satisfaction between single and coupled emerging adults in the LGBT community

The target participants for this research is LGBT emerging adults, aged 18 to 21. There is inadequate literature that compares single individuals and those who are in a relationship-- especially when it comes to the LGBT community. This research sought to fill in gap in research and find differences between single and coupled Filipino LGBT emerging adults in terms of stigma, discrimination, and life satisfaction. Data was gathered primarily by disseminating psychological scales that measure the dependent variables (stigma, discrimination, and life satisfaction) to 110 Filipino LGBT emerging adults. Using t-test for comparison of means, the findings show that there is no significant difference between the two independent groups (Single Group and In a relationship Group) when it comes to stigma and discrimination. However, life satisfaction levels exhibit a significant difference between the two groups wherein the relationship group resulted in higher life satisfaction levels. The theoretica framework presented in this research served as a basis for providing explanations for the findings. The researchers are employed qualitative methods to further enrich the discussion as there is extremely limited literature to justify the results. A recurring theme that the participations had shared is the immense influence of Catholicism in the Philippines, which plays a major role in the difficulty of accepting LGBT individuals wholeheartedly-- regardless of whether they are single or not

Do Preoperative Esophageal pH Monitoring and High-Resolution Manometry Predict Symptoms of GERD After Sleeve Gastrectomy?

International audienceBackground: Predictive factors of evolution or appearance of gastroesophageal reflux disease (GERD) after sleeve gastrectomy (SG) have not been identified to date. We aimed to assess the evolution of GERD symptoms 1 year after SG and to determine preoperative predictive factors using high-resolution manometry (HRM) and ambulatory 24-h esophageal pH monitoring (APM).Methods: We included 160 patients who underwent SG between 2013 and 2017 and performed preoperative APM and HRM. Positive APM was defined according to the Lyon consensus. Symptoms of GERD, proton pump inhibitors (PPI) use, weight loss (WL), and diet were recorded in all patients before and 1 year after surgery.Results: One year after surgery, 58 patients (36.3%) complained of GERD symptoms compared to 52 patients (32.5%) preoperatively (p=0.48). Among patients with preoperative GERD symptoms, only 26/52 patients (50%) still had symptoms, whereas 32/108 (29.6%) asymptomatic patients developed de novo GERD symptoms after surgery. PPI use increased after surgery reaching 36.9% of patients against 15.0% before (p<0.0001). Only preoperative symptoms of GERD were predictive of postoperative symptoms (OR= 2.47 [1.14-5.45]; p=0.023) in multivariate analysis. Preoperative manometric parameters, postoperative diet, and WL were not related to postoperative symptoms. In asymptomatic patients before surgery, silent GERD (positive APM without symptom) was predictive of postoperative GERD symptoms (OR=2.69 [1.00-7.25]; p=0.049).Conclusion: Evolution of GERD symptoms after SG reveals improvement for half of the patients and de novo GERD symptoms in one-third of patients. Predictive factors of postoperative symptoms are preoperative symptoms and positive preoperative APM in asymptomatic patients

Usutu Virus Isolated from Rodents in Senegal

Usutu virus (USUV) is a Culex-associated mosquito-borne flavivirus of the Flaviviridae family. Since its discovery in 1959, the virus has been isolated from birds, arthropods and humans in Europe and Africa. An increasing number of Usutu virus infections in humans with neurological presentations have been reported. Recently, the virus has been detected in bats and horses, which deviates from the currently proposed enzootic cycle of USUV involving several different avian and mosquito species. Despite this increasing number of viral detections in different mammalian hosts, the existence of a non-avian reservoir remains unresolved. In Kedougou, a tropical region in the southeast corner of Senegal, Usutu virus was detected, isolated and sequenced from five asymptomatic small mammals: Two different rodent species and a single species of shrew. Additional molecular characterization and in vivo growth dynamics showed that these rodents/shrew-derived viruses are closely related to the reference strain (accession number: AF013412) and are as pathogenic as other characterized strains associated with neurological invasions in human. This is the first evidence of Usutu virus isolation from rodents or shrews. Our findings emphasize the need to consider a closer monitoring of terrestrial small mammals in future active surveillance, public health, and epidemiological efforts in response to USUV in both Africa and Europe